Re: [DML] Rear Calipers on Ebay

["Harold McElraft" <hmcelraft@xxxxxxx>]

Actually from the physics thing - I think you will find that force 
being applied at the caliper from the brake pedal is unchanged and 
the pistons are the distribution medium. Therefore, the force is the 
same it is just being distributed over a smaller area. Does that make 
a difference in the braking? I don't know because the action on the 
pads would have to be evaluated - but, I doubt if much is lost.

Harold McElraft - 3354


--- In dmcnews@xxxxxxxxxxxxxxx, "Tom Tait" <TTait@...> wrote:
>
> (note - I'm not an automotive engineer, but this is pretty basic 
physics
> and common sense)
> 
>  
> 
> If one uses the same brake pads, then the stopping power will be a
> factor of how hard those pads are pressed onto the rotor.
> 
>  
> 
> You could compensate for a smaller piston by pressing harder (5% I'm
> guessing without doing the math) and get similar braking results 
with
> the following caveats:
> 
>  
> 
> If you can't push hard enough to nearly lock up your brakes, then 
you
> are not reaching your full braking power - its' unlikely that 5% 
would
> make a difference for most drivers, but it could.  Once you push 
hard
> enough to lock up the brakes, its all equal anyway.
> 
>  
> 
> The smaller rear calipers will shift more of your braking power to 
the
> front of the car, but not as much as the saab master would shift it.
> 
>  
> 
> A smaller caliper pushing into the back of the pad may distribute 
the
> force onto that pad differently than the larger one would, causing
> slightly decreased performance or pad life, particularly as the pad
> wears thin.
> 
>  
> 
> How you feel about this stuff depends on how you drive your car, and
> what you expect from your brakes that one time every 5 years that 
this
> might make a big difference.
> 
>  
> 
> My understanding is that the castings are nearly identical, and 
coming
> from the same factory.  Based on the production dates it seems that 
the
> Jag brakes pre-date the Delorean brakes.  What is it about that 5mm
> difference that made the original engineer at Delorean, who had to 
make
> the call, decide to go with a new casting and part, rather than an
> existing one?  Maybe it was so the parts department at the Delorean
> Dealers could charge more for their part, or maybe it really makes a
> difference.  
> 
>  
> 
> They are your brakes, it's your wallet and your butt in the seat.  
I'm
> not sure myself if the difference is really that important to the 
casual
> driver,  but I think John is doing service to more than his own 
business
> by pointing out that there are differences and letting us all 
decide if
> or how they affect us/
> 
>  
> 
> Like most things here - you have to make that final determination
> yourself.
> 
>  
> 
>  
> 
> From: dmcnews@xxxxxxxxxxxxxxx [mailto:dmcnews@xxxxxxxxxxxxxxx] On 
Behalf
> Of DMCVIN6683
> Sent: Wednesday, March 28, 2007 7:02 PM
> To: dmcnews@xxxxxxxxxxxxxxx
> Subject: Re: [DML] Rear Calipers on Ebay
> 
>  
> 
> Why wouldn't these work correctly?
> 
> Some of us have been using the wrong Master Cylinder for years with 
> no problems that has been proportioned all wrong so who is it to 
say 
> these Calipers wont do the job being 5mm smaller?
> 
> Mark V
> 
> On Mar 28, 2007, at 6:38 PM, John Hervey wrote:
> 
> > Group,
> > If you were bidding on or purchased rear calipers on ebay in the 
last
> > month I have some sad new. They are not DeLorean they are Jaguar.
> > Don't buy them and don't use them and don't put them on your car
> > unless you can confirm they are DeLorean.
> > I don't think the seller did it on purpose but I did send an email
> > and never got a reply.
> > I bought a set and got them in today and confirmed they are 
Jaguar.
> > The difference is the rear Delorean caliper pistons are 48mm in
> > diameter and the Jaguar are 43mm in diameter. That doesn't sound 
like
> > much, but it could make a big difference in a jam not having that 
> > extra
> > 5mm size and volume for stopping.
> > Bidder #3 also bought some.
> > So be careful and ask before you buy any rear caliper.
> > For those of you that have ordered from Autozone or other Box 
stores,
> > you to may have got the wrong part also. I have heard some people
> > boasting on other chat groups that they bought DeLorean calipers 
and
> > how much money they saved. I don't think you got DeLorean. You 
either
> > got Mercury Capri on the front and Jaguar on the back.
> > John Hervey
> > www.deloreanautoparts.com
> > www.specialtauto.com
>




To address comments privately to the moderating team, please address:
moderators@xxxxxxxxxxx

For more info on the list, tech articles, cars for sale see www.dmcnews.com

To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/dmcnews/

<*> Your email settings:
    Individual Email | Traditional

<*> To change settings online go to:
    http://groups.yahoo.com/group/dmcnews/join
    (Yahoo! ID required)

<*> To change settings via email:
    mailto:dmcnews-digest@xxxxxxxxxxxxxxx 
    mailto:dmcnews-fullfeatured@xxxxxxxxxxxxxxx

<*> To unsubscribe from this group, send an email to:
    dmcnews-unsubscribe@xxxxxxxxxxxxxxx

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/